In known conductor line systems, a movable electrical load travels along a conductor line. The supply of the load with electrical energy here occurs via a current collecting device whose sliding contacts engage conductor strands of the conductor line. The load can be, for example, a transport box of an overhead track conveyor, a cable trolley that can travel on rails, or also so-called E-RTG container cranes that are equipped with an electrical drive that is supplied with electrical energy by the conductor line.
U.S. Pat. No. 3,396,246 A discloses a current collecting device for an electrical load that can travel along a contact wire, with two sliding contact pieces arranged after one another, each on its own lever arm. The two arms are arranged in each case on a fork bearing in such a manner that they can rotate about a common rotation axis, and they are pulled closed, towards one another, by two coil springs. The ends of the coil springs here are led in each case through openings in the arms. The separate arrangement of the two arms is expensive and requires the installation of two respective coil springs.
U.S. Pat. No. 1,826,854 A discloses a current collecting device for electrical loads that can move along a contact wire, which can tap current from the contact wire by means of two running rollers arranged consecutively. Here, the current collecting rollers are connected to sliding contacts of a conductor ring arrangement via short supply lines. The contact surfaces of the sliding contact ring arrangement, which are stationary relative to the sliding contacts, are arranged on an arm, which itself is arranged above a base. Supply lines extend from the stationary contact surfaces of the sliding contact ring arrangement to a second sliding contact ring arrangement arranged on the base. This construction is expensive due to the two sliding contact ring arrangements, and, at least in the area of the first sliding contact ring arrangement, which is not shielded relative to the exterior, it is contact-endangered.
EP 0 226 497 B1 discloses a current collecting head for a trolley bus, in which the lines are led between a sliding contact that can be rotated through a large angle and a connection clamp, in part in a rotating arm of the current collecting device and in part exposed in open areas. In the open areas, the lines risk being damaged from the outside or being caught. Moreover, the lines are not led in a defined manner or fastened between a sliding contact and a connection clamp, so that they impede the movements of the arm and of the sliding contact due to their current position. In addition, the lines are continually moved back and forth as a result, so that the electrically conductive line cores can be damaged and the insulations can be abraded. Thus, there is also a risk of injury to persons, if the line cores are exposed in places.
In addition, the movement of the sliding contact is limited only by two end abutments. At best, an automatic resetting into a preferred resting position with good contact on the conductor strand of the conductor line is provided by the lines that are led haphazardly through the current collecting head.
DE 30 18 428 A1 discloses a control current transferring device with a contact sensor arrangement for trolleys in conveyor systems, which is in springy contact with the control current rail. There too, the control current lines are only partially protected and largely led freely movably through an elongate housing. Here too, there is the risk that the control current lines or their insulation could be damaged due to continual movements of the control current transferring device and the contact sensor arrangement.
In JP S63-202202 A, in the case of a current collecting device for conductor lines, the connection line to the sliding contact pieces is also largely free and attached only at one site of the current collecting device to a clip made of a metal plate. Here, it is precisely in the area of the clip that there is a risk of the sharp metal plate damaging the insulation of the line. Otherwise the risk also exists of the line being caught or migrating.
In EP 1 352 777 A1 as well, in a current collecting device for conductor lines, the exposed line extends away from the sliding contact, so that here, too, there is an increased risk of damage.
DE 36 10 455 A1 discloses a current collecting head with two sliding contact pieces arranged on a rocker mounted in manner so it can rotate. A tilting area of the rocker is limited by abutments on the bearing of the rocker. However, between the abutments, the rocker can be moved freely back and forth, so that no optimal contact on the conductor strand of the conductor line is ensured. There, the connecting line also extends largely exposed and unprotected away from the sliding contact pieces.